ISA Operator for Event Queries
The ISA operator is a WQL-specific operator that can be used in event queries. When ISA is included in the WHERE clause of an event query, it requests notification of events for all classes within a class hierarchy, rather than a specific event class.
The following example requests notification every 10 minutes of instance modification events for all instances that are members of any class derived from the Win32_LogicalDisk class.
SELECT * FROM __InstanceModificationEvent WITHIN 600 WHERE TargetInstance ISA "Win32_LogicalDisk"